code: def test_main_returns_2_on_empty(self):
      with pytest.raises(SystemExit) as cm:
          with capture_sys_output() as (stdout, stderr):
              nipype_cmd.main(["nipype_cmd"])
  
      exit_exception = cm.value
      assert exit_exception.code == 2
  
      msg = """usage: nipype_cmd [-h] module interface
  nipype_cmd: error: the following arguments are required: module, interface
  """
  
      assert stderr.getvalue() == msg
      assert stdout.getvalue() == ""
  
file_path: nipype/nipype/utils/tests/test_cmd.py
imports: import pytest
  import sys
  from contextlib import contextmanager
  from io import StringIO
  from ...utils import nipype_cmd
label_desc: Use image node_id 1 for calling the TestNipypeCMD obj's underlying member method code with example usage: obj.test_main_returns_2_on_empty() without return types